let i be Element of NAT ; for m, n being non empty Element of NAT
for F being PartFunc of (REAL-NS m),(REAL-NS n)
for G being PartFunc of (REAL m),(REAL n)
for x being Point of (REAL-NS m)
for y being Element of REAL m st F = G & x = y & F is_partial_differentiable_in x,i holds
(partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
let m, n be non empty Element of NAT ; for F being PartFunc of (REAL-NS m),(REAL-NS n)
for G being PartFunc of (REAL m),(REAL n)
for x being Point of (REAL-NS m)
for y being Element of REAL m st F = G & x = y & F is_partial_differentiable_in x,i holds
(partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
let F be PartFunc of (REAL-NS m),(REAL-NS n); for G being PartFunc of (REAL m),(REAL n)
for x being Point of (REAL-NS m)
for y being Element of REAL m st F = G & x = y & F is_partial_differentiable_in x,i holds
(partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
let G be PartFunc of (REAL m),(REAL n); for x being Point of (REAL-NS m)
for y being Element of REAL m st F = G & x = y & F is_partial_differentiable_in x,i holds
(partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
let x be Point of (REAL-NS m); for y being Element of REAL m st F = G & x = y & F is_partial_differentiable_in x,i holds
(partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
let y be Element of REAL m; ( F = G & x = y & F is_partial_differentiable_in x,i implies (partdiff (F,x,i)) . <*1*> = partdiff (G,y,i) )
assume that
A1:
F = G
and
A2:
x = y
and
A3:
F is_partial_differentiable_in x,i
; (partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
A4:
the carrier of (REAL-NS n) = REAL n
by REAL_NS1:def 4;
the carrier of (REAL-NS 1) = REAL 1
by REAL_NS1:def 4;
then
partdiff (F,x,i) is Function of (REAL 1),(REAL n)
by A4, LOPBAN_1:def 9;
then A5:
(partdiff (F,x,i)) . <*1*> is Element of REAL n
by FINSEQ_2:98, FUNCT_2:5;
G is_partial_differentiable_in y,i
by A1, A2, A3, Th16;
hence
(partdiff (F,x,i)) . <*1*> = partdiff (G,y,i)
by A1, A2, A5, Def14; verum